Analysis of Uranium Bearing Samples for Rare Earth and Other Elements by k₀-Based Internal Monostandard INAA Method

Abstract

A k₀-based internal monostandard instrumental neutron activation analysis (IM-INAA) method was applied for the multielement analysis in uranium bearing samples. Spectral interference correction factors in INAA due to neutron induced fission of uranium for La, Ce, Nd, Zr, Ru, and Mo as well as activation of uranium for Sm and Lu were evaluated using elemental standards. The correction factors were validated by standard addition method in a synthetic sample containing known amount of natuural uranium. For evaluating the accuracy of the IM-INAA method, the low uranium containing SRM 1633a (coal fly ash) obtained from NIST was used. For method validation of analysis of uranium bearing sample, SRM 1633a spiked with uranium (about 0.05%) was analyzed by IM-INAA method. The standardized IM-INAA method was applied to analyze uranium ore samples obtained from Jaduguda and Bhatin mines, Jharkhand, India for multielement content including U, Th, and rare earth elements (REEs). Chondrite normalized REE patterns were plotted for obtaining Ce and Eu anomalies.